Effect of hypothermia on polarization of microglia and TLR4/NF-κB signaling pathway during oxygen-glucose deprivation/restoration
10.3760/cma.j.cn131073.20211115.00916
- VernacularTitle:低温对小胶质细胞氧糖剥夺/复糖复氧时细胞极化及TLR4/NF-κB信号通路的影响
- Author:
Kaiyue SHAN
1
;
Miao XIN
;
Rui DONG
;
Huailong CHEN
;
Gaofeng ZHANG
;
Wenjie LIU
;
Mingshan WANG
Author Information
1. 大连医科大学研究生院,大连 116044
- Keywords:
Hypothermia, induced;
Microglia;
Reperfusion injury;
Toll-Like receptor 4;
NF-kappa B;
Polarization
- From:
Chinese Journal of Anesthesiology
2022;42(9):1098-1102
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To evaluate the effect of hypothermia on the polarization of microglia and TLR4/NF-κB signaling pathway during oxygen-glucose deprivation/restoration (OGD/R).Methods:BV2 microglia were cultured in vitro and divided into 3 groups ( n=18 each) using the random number table method: control group (group C), group OGD/R and OGD/R plus hypothermia group (group OGD/R+ HT). Group C was cultured normally for 24 h. In group OGD/R, the cells were exposed to 5% CO 2-1% O 2 at 37 ℃ for 2 h in a glucose-free medium, followed by restoration of glucose and oxygen for 24 h. In group OGD/R+ HT, the high-glucose medium was replaced with a glucose-free medium, the cells were exposed to 5% CO 2-1% O 2 for 2 h in a 33 ℃ cryostat, followed by restoration of glucose and oxygen for 24 h. The cell survival rate was measured by CCK-8 assay.The expression of M1 microglia markers CD32 and iNOS protein and mRNA and M2 microglia markers CD206 and Arg-1 and mRNA was detected by immunofluorescence and real-time quantitative polymerase chain reaction.The expression of TLR-4 and NF-κB in cells was detected by Western blot, and the expression of TLR4 and NF-κB mRNA in cells was detected by real-time quantitative polymerase chain reaction.The concentrations of tumor necrosis factor α (TNF-α), interleukin 1β (IL-1β) and interleukin 10 (IL-10) in the cell supernatant were detected by enzyme-linked immunosorbent assay. Results:Compared with group C, the cell survival rate was significantly decreased, the expression of CD32, iNOS, CD206, Arg-1, TLR4 and NF-κB protein and mRNA was up-regulated, and the concentrations of TNF-α, IL-1β and IL-10 in supernatant were increased in OGD/R and OGD/R+ HT groups ( P<0.05). Compared with group OGD/R, the cell survival rate was significantly increased, the expression of CD32, iNOS, TLR4 and NF-κB protein and mRNA was down-regulated, the expression of CD206 and Arg-1 protein and mRNA was up-regulated, the concentrations of TNF-α and IL-1β in supernatant were decreased, and the concentration of IL-10 was increased in group OGD/R+ HT ( P<0.05). Conclusions:Hypothermia can significantly inhibit microglia polarization toward M1 phenotype, increase microglia polarization toward M2 phenotype and inhibit the development of inflammatory responses during OGD/R, and the mechanism may be related to inhibition of TLR4/NF-κB signaling pathway.